textproduct: Albany

WHAT HAS CHANGED

Continued trend from previous forecast of increasing wind gusts today, increasing cloud cover across northern areas, and bumping up PoPs for northern areas through this evening.

Also, for the Monday system, some of the 12 guidance has trended further north with the QPF shield. It remains to be seen if this is the start of a larger trend or not, but will note that the axis of heaviest rainfall could shift north over the next couple of forecast cycles if this trend continues.

KEY MESSAGES

1) Isolated/scattered showers and thunderstorms expected today and Sunday mainly for areas along north and east of the Greater Capital Region and Berkshires.

2) High confidence for a widespread soaking rainfall across portions of eastern NY/western New England Monday into Tuesday, but the exact location of where the heaviest rainfall occurs is still uncertain. This will be a largely beneficial rainfall for most areas, although minor flooding in urban/poor drainage areas is possible.

DISCUSSION

KEY MESSAGE 1...Our region remains under broad upper troughing and a cold pool aloft. This is leading to ~500 J/KG of MLCAPE across northern portions of our area, which has allowed for some scattered showers and a few thunderstorms to develop. While some small hail can't totally be ruled out due to steep low- level lapse rates and low (<8000 ft) WBZ heights, a lack of wind shear should prevent a severe threat with any of these storms. Best chance for a shower/storm will be in the W/NW upslope areas of the southern ADKs and southern Greens, but the rest of the upper Hudson Valley in between could still see some scattered showers or a storm as well. Showers and storms diminish this evening with the loss of daytime heating.

Tomorrow, setup will be similar to today, but with a few key differences. An approaching upper shortwave will provide better upper forcing for ascent, although there will be more mid-level dry air in place that could stifle convective initiation. Therefore, there is some uncertainty as to coverage of showers/storms tomorrow afternoon. Have stuck near NBM, which gives slight chance to chance for most of the region, with likely PoPs across the high terrain areas north of I-90. While deep-layer shear is marginally better tomorrow, shear should still be low enough to prevent any severe threat. Showers and storms once again diminish Sunday evening with the loss of diurnal heating. Sunday temperatures will be similar or a couple degrees warmer vs today, with lows again in the 40s to 50s.

KEY MESSAGE 2... Monday, a sfc low will track through the Ohio Valley along a stalled frontal boundary in response to an upper shortwave aloft. A strengthening southerly LLJ ahead of this system will lead to moisture transport into our region, with PWATs climbing to around 1.75" for southern areas. This moisture will overlap with a fairly impressive sloping band of mid-level FGEN, along with decent upper forcing from the shortwave and the right entrance region of a jet streak to our north. So, expecting widespread rain/showers to overspread the region Monday/Monday afternoon, continuing through Monday night before tapering off Tuesday as the system departs to our east.

Some of the 12z guidance has trended further north with the track of the sfc low and thus the heaviest rainfall. Will have to see if this is the beginning of a larger trend or more of a blip. At this time, have therefore stuck near NBM QPF, which has a widespread 1" or more of rain near and south of I-90, with up to 2" near the I-84 corridor and in western CT. Should north trend continue, then the axis of heaviest rain could be shifted further north into our area.

As for impacts, this generally looks like a beneficial rain. The heaviest rain is expected to fall near and south of I-90. Much of this area has missed out on the heavier rain with the convection over the past few days, with D0 to D1 drought conditions there per the latest drought monitor. At this time, there does not look to be much in the way of instability leading to enhanced rainfall rates. So, potential for hydro issues still appears low, aside from some nuisance ponding of water in the typical urban/poor drainage areas. WPC indicated that they plan to introduce a slight risk ERO clipping out I-84 corridor, but this seems to be more based on the worst-case scenario that would only be realized if the more northern storm track were to verify and allow a tongue of elevated instability to reach into our area. At this time, this more northern solution does not appear to be the most likely outcome, but cannot be completely ruled out either. Will obviously continue to monitor forecast trends over the next couple days, and should be able to provide some more detail on location of heaviest rainfall amounts as more hi-res guidance becomes available.

Rain comes to an end Tuesday, with drier conditions expected Wednesday aside from an isolated shower under the lingering upper trough. Low confidence on additional rain chances Thursday/Friday, as another upper trough will be approaching with more moisture, although timing remains highly uncertain this far out. After a cool day Monday, temperatures generally look to remain near to perhaps slightly above normal for the middle and end of next week.

AVIATION /00Z SUNDAY THROUGH THURSDAY/

Through 00Z Monday...VFR conditions through 06 UTC at all terminals as skies clear. There is medium confidence that the ensuing radiational cooling tonight will support fog formation at GFL between 07 and 11 UTC which we continued to message in a TEMPO group. Otherwise, diurnally driven clouds develop by 15 - 17 UTC with cigs around 5kft with a chance for isolated to widely scattered once again by 17 and 22 UTC/Sunday mainly at POU, PSF and GFL. ALB looks to miss out on these showers. During any shower, MVFR vis is possible from brief heavy downpours. Did not include thunder at this time but will continue to monitor trends. We may need to include VCTS in future updates given weak instability.

Winds weaken this evening but remain sustained 5-10kts overnight except at GFL where winds should turn light and variable. Westerly winds strengthen again by 12 - 15 UTC with sustained winds 5-12kts and gusts up to 20kts.

Outlook...

Sunday Night: No Operational Impact. NO SIG WX. Monday: High Operational Impact. Definite SHRA...TSRA. Monday Night: High Operational Impact. Definite SHRA...TSRA. Tuesday: Moderate Operational Impact. Chance of SHRA. Tuesday Night: No Operational Impact. NO SIG WX. Wednesday: No Operational Impact. NO SIG WX. Wednesday Night: No Operational Impact. NO SIG WX. Thursday: Moderate Operational Impact. Chance of SHRA...TSRA.

ALY WATCHES/WARNINGS/ADVISORIES

CT...None. NY...None. MA...None. VT...None.